Search Publications
Spin and activity of comet 67P/Churyumov-Gerasimenko
Lara, L. M.; Sierks, H.; Vincent, J. -B. +2 more
Aims: In 2014 ESA's spacecraft Rosetta will reach its final target: comet 67P/Churyumov-Gerasimenko (67P). Although this comet has been studied in great detail over the past decade, there are still some uncertainties regarding the actual spin orientation and the distribution of active regions on the surface. We here give an overview of our cu…
Active galactic nucleus torus models and the puzzling infrared spectrum of IRAS F10214+4724
Siebenmorgen, R.; Verma, A.; Efstathiou, A. +1 more
We present a revised model for the infrared emission of the hyperluminous infrared galaxy IRAS F10214+4724 which takes into account recent photometric data from Spitzer and Herschel that sample the peak of its spectral energy distribution. We first present and discuss a grid of smooth active galactic nucleus (AGN) torus models computed with the me…
Detection of a plasmaspheric wind in the Earth's magnetosphere by the Cluster spacecraft
Dandouras, I.
Plumes, forming at the plasmapause and released outwards, constitute a well-established mode for plasmaspheric material release to the Earth's magnetosphere. They are associated to active periods and the related electric field change. In 1992, Lemaire and Shunk proposed the existence of an additional mode for plasmaspheric material release to the …
Comparative magnetotail flapping: an overview of selected events at Earth, Jupiter and Saturn
André, N.; Jackman, C. M.; Nakamura, R. +9 more
A comparison of magnetotail flapping (the up-and-down wavy motion) between the Earth and the two giant planets Jupiter and Saturn has been performed through investigation of the current sheet normal of the magnetotail. Magnetotail flapping is commonly observed in the Earth's magnetotail. Due to single spacecraft missions at the giant planets, the …
Deep Multi-telescope Photometry of NGC 5466. I. Blue Stragglers and Binary Systems
Dalessandro, E.; Bellazzini, M.; Beccari, G. +4 more
We present a detailed investigation of the radial distribution of blue straggler star (BSS) and binary populations in the Galactic globular cluster NGC 5466, over the entire extension of the system. We used a combination of data acquired with the Advanced Camera for Survey on board the Hubble Space Telescope, the LBC-blue mounted on the Large Bino…
GAMA/H-ATLAS: linking the properties of submm detected and undetected early-type galaxies - I. z ≤ 0.06 sample
Ivison, R. J.; Häußler, B.; Cooray, A. +34 more
We present two large, nearby (0.013 ≤ z ≤ 0.06) samples of early-type galaxies (ETGs): a visually classified sample of 220 ETGs, created using source-matched data from the Galaxy and Mass Assembly (GAMA) data base with far-infrared/submm detections from Herschel-Astrophysical Terahertz Large Area Survey (H-ATLAS); and a visually classified sample …
Observable Effects of Interplanetary Coronal Mass Ejections on Ground Level Neutron Monitor Count Rates
Rodríguez-Pacheco, J.; Hidalgo, M. A.; Blanco, J. J. +3 more
In this work, non-recurrent Forbush decreases (FDs) triggered by the passage of shock-driving interplanetary coronal mass ejections (ICMEs) have been analyzed. Fifty-nine ICMEs have been studied, but only 25 % of them were associated to a FD. We find that shock-driving magnetic clouds (MCs) produce deeper FDs than shock-driving ejecta. This fact c…
A Double-peaked Outburst of A 0535+26 Observed with INTEGRAL, RXTE, and Suzaku
Klochkov, D.; Santangelo, A.; Wilms, J. +18 more
The Be/X-ray binary A 0535+26 showed a normal (type I) outburst in 2009 August. It is the fourth in a series of normal outbursts associated with the periastron, but is unusual because it presented a double-peaked light curve. The two peaks reached a flux of ~450 mCrab in the 15-50 keV range. We present results of the timing and spectral analysis o…
Direct Determination of the HF/H2 Abundance Ratio in Interstellar Gas
Neufeld, D. A.; Richter, M. J.; Indriolo, Nick +1 more
We report the first detection of the v = 1-0, R(0) ro-vibrational transition of HF at 2.499385 µm arising from interstellar gas. The line is seen in absorption toward three background sources—HD 154368, Elias 29, and AFGL 2136 IRS 1—all of which have reported H2 column densities determined from observations of H2. This …
Venus ion outflow estimates at solar minimum: Influence of reference frames and disturbed solar wind conditions
Barabash, S.; Zhang, T. L.; Nilsson, H. +2 more
Recent estimates of ion escape rates from Venus, based on ASPERA-4 data, differ by more than a factor of 4. Whereas the ASPERA-4 instrument provides state-of-the art observations, the limited field of view of the instrument and the strongly limited geographical coverage of the spacecraft orbit means that significant assumptions must be used in the…